Single-use bioreactor systems are commonly used for cell culture applications. The growth and culture of mammalian cells, for instance, typically require a constant supply of adequate oxygen. Oxygen diffusion in culture media is a function of a liquid-to-air surface area when operating the bioreactor. Furthermore, oxygen transfer is limited by the liquid-to-air surface area and any shear forces created by agitation and/or sparging.
Both bubbling and agitation typically have a detrimental effect on biological cells, such as mammalian cell cultures. Biological cells may be rendered non-viable through bubble breakup and/or coalescence within the culture media, especially at a surface gas-to-liquid interface. Therefore, maximizing oxygen transfer in the bioreactor must be balanced by maintaining cell viability.
A rocking motion of the bioreactor promotes wave formation in the bag which provides liquid mixing and enhances oxygen transfer. Additionally, the bioreactor provides an excellent environment for cell growth and expression due to the low shear generated by the gentle wave agitation and bubble-free aeration system.